This invention relates to a solid-state color imaging apparatus.
An interline transfer CCD imaging element (hereinbelow, abbreviated to "IL-CCD imaging element") comprises a plurality of picture elements arrayed regularly in both a horizontal direction and a vertical direction. Vertical CCD registers transfer, in the vertical direction, signal charges which are photoelectrically converted by and stored in the picture elements. At the ends of the vertical column, a horizontal CCD register transfers them in the horizontal direction to an output portion.
The IL-CCD imaging element is capable of two sorts of read-out operations which are a frame storage operation in which the signal charges stored in the picture elements are read out during every frame period, and a field storage operation in which they are read out during every field period. The field storage operation requires a half of the frame storage time, and gives a lesser feeling of afterimage. For this reason, the development of a single-plate color imaging device for effecting the field storage operation is being promoted.
In color imaging by the use of the IL-CCD imaging element, the color separated images of a subject are formed by color filters. The color separated images are picked up by the IL-CCD imaging element. The output signals of the IL-CCD imaging element are processed, thereby to obtain chrominance and luminance signals.
A conventional IL-CCD imaging apparatus having a conventional color filter has a disadvantage, to be described below. The signal of each horizontal line is a sum of the signal charges obtained by independently and spatially sampling the two adjacent picture elements in the vertical direction and is not constituted by a single horizontal line signal. This causes a very large vertical color error in the output signal of the conventional imaging apparatus when the apparatus picks up a subject having a vertical repetition frequency equal to one half of the number of the vertical picture elements, that is, a sharp vertical contour portion having no vertical correlation between two adjacent horizontal picture element rows.